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� <br /> ~ - <br /> ` <br /> It is necessary to multiply the time available since the � <br /> spill by the coefficient of permeability ( a velocity ) , to <br /> determine the approximate distance the supposed oil contamination <br /> might have traveled. Since we have no field measurement of <br /> permeability at this time, for these soils, it would be best to . <br /> assign a range of permeabilities to the soils. From the chart <br /> . above, a range of 10 to the minus 5 to 10 tothe minus 7 teems ` <br /> appropriate. The results fbllow: . <br /> ASSUMED PERMEABILITY DIST TRAV IN CM DIST TRAV IN FT ' <br /> 10 to minus 5 470. 0 15. 416 ` <br /> 10 to minus <br /> 47 0 ' 1 5416 <br /> 6 . . <br /> 10 to minus 7 4. 7 0. 15416 ' <br /> It is important to realize that the coefficients of � <br /> permeability shown in the chart above assume a hydraulic gradient . <br /> of 1 . The hydraulic gradient as measured in the field for this <br /> site ranges between . 0014 and .0127, considerably less than 1 . � <br /> Actual coefficients of permeability should be less than these <br /> shown. � <br /> Using the above logic, one can say that most likely the <br /> contamination resulting from the oil spill at this site has not <br /> traveled more than 15 feet from the area where the spill . <br /> occurred. Therefore, the most likely place to site an additional � <br /> monitoring well would be within a circle of 15 foot radius from <br /> the point where the spill occurred. This logic relies heavily on <br /> the assumption that actual field permeabilities ( which can be <br /> measured , but have not been at present ) are within the ranges <br /> shown above. <br /> It appears then, that the contamination resulting from this <br /> spill could not have traveled very far from the point of origin. <br /> We can inferr this based on definite knowledge of the soils <br /> geology of the site, and on knowledge of the general hydraulic <br /> properties of these types of soils. <br /> - <br /> 5 <br />